Investigation of Quinoline Derivatives as Corrosion Inhibitors for Mild ...

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Scholars Research Library Der Pharmacia Lettre, 2016, 8 (18):158-166 (http://scholarsresearchlibrary.com/archive.html) ISSN 0975-5071 USA CODEN: DPLEB4

Investigation of Quinoline Derivatives as Corrosion Inhibitors for Mild Steel in HCl 1.0 M H. Lgaz1,2, M. Saadouni3, R. Salghi2*, S. Jodeh4, M. Elfaydy5, B. Lakhrissi5, S. Boukhris3 and H. Oudda1 1

Laboratory of separation methods, Faculty of Science, University Ibn Tofail PO Box 242, Kenitra, Morocco Laboratory of Applied Chemistry and Environment, ENSA, Université Ibn Zohr,PO Box 1136, 80000 Agadir, Morocco 3 Laboratory of Organic, Organometallic and Theoretical Chemistry, Faculty of Science, Ibn Tofaïl University, 14000 Kenitra, Morocco 4 Department of Chemistry, An-Najah National University, P. O. Box 7, Nablus, Palestine 5 Laboratoire d’Agroressources, Polymères et Génie des Procédés, University Ibn Tofail PO Box 242, Kenitra, Morocco _____________________________________________________________________________________________ 2

ABSTRACT The influence of three quinoline derivatives (8QNs) namely, ethyl 2-(((8-hydroxyquinolin-5-yl)methyl)amino)acetate (8QN1), 5-((benzylamino)methyl)quinolin-8-ol (8QN2) and 5-(azidomethyl)quinolin-8-ol (8QN3) on the mild steel corrosion in 1 M HCl was studied by weight loss and electrochemical methods. Results showed that 8QN3 shows maximum inhibition efficiency of 90% at 5×10-3 M concentration. Polarization study revealed that the 8QNs act as mixed type inhibitors. EIS measurements showed that the studied compounds inhibit mild steel corrosion by adsorbing on the steel surface. Results showed that inhibition efficiency increases with concentration. Adsorption of 8QNs on the mild steel surface obeyed the Langmuir adsorption isotherm. Keywords: Mild steel, Corrosion, HCl, Quinoline derivatives, EIS, Polarization, Thermodynamic study. _____________________________________________________________________________________________ INTRODUCTION Corrosion is defined as degradation of metals as a result of chemical reaction with the surrounding environment. Corrosion causes heavy economic losses. In the United States, the economic losses reported in 1998 were $276 billion per year which is now exceeds to $1 trillion dollars a year. Mild steel is widely used metal in industries because of its high strength, ease of fabrication and cost-effectiveness[1–6]. However it suffers from corrosion during acid cleaning, pickling, and descaling. Hydrochloric acid solution is used to enhance oil recovery during acidization[7–14]. The damage by corrosion generates not only high cost for renovation, replacement of various equipments, but in addition these constitute a public risk. Thus it is necessary to develop some effective corrosion inhibitors. The emphasis on the selection of corrosion inhibitor is based on the electron rich functional groups along with π-electrons inside their frameworks. Earlier various organic compounds have been reported as corrosion inhibitors[11–19]. Generally, organic inhibitors inhibit metallic corrosion by adsorbing on the surface and thereby forming a protective barrier between metal and electrolyte (1 M HCl)[20–23]. The adsorption of these inhibitors on metallic surface are influenced by several factors such as molecular size of inhibitor, nature of substituents, nature of metal and electrolyte[24–28]. Organic compounds containing heteroatoms including nitrogen, sulfur, and/or oxygen with polar functional groups and conjugated double bonds have been reported as effective corrosion inhibitor[29– 32].

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R. Salghi et al Der Pharmacia Lettre, 2016, 8 (18):158-166 ______________________________________________________________________________ The compounds with quinolone functions are rarely investigated such as corrosion inhibitors[33,34]. Therefore, it is necessary to study the corrosion inhibition effect and inhibition mechanism of the quinoline derivatives which could be deemed as good potential inhibitors. In view of this, three synthesized quinolone derivatives namely ethyl 2-(((8-hydroxyquinolin-5yl)methyl)amino)acetate (8QN1), 5-((benzylamino)methyl)quinolin-8-ol (8QN2) and 5-(azidomethyl)quinolin-8-ol (8QN3) were synthesized to study mild steel corrosion inhibition in 1 M HCl using weight loss, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. MATERIALS AND METHODS Materials The steel used in this study is a mild steel (Euronorm: C35E carbon steel and US specification: SAE 1035) with a chemical composition (in wt%) of 0.370 % C, 0.230 % Si, 0.680 % Mn, 0.016 % S, 0.077 % Cr, 0.011 % Ti, 0.059 % Ni, 0.009 % Co, 0.160 % Cu and the remainder iron (Fe). The mild steel samples were pre-treated prior to the experiments by grinding with emery paper SiC (120, 600 and 1200); rinsed with distilled water, degreased in acetone in an ultrasonic bath immersion for 5 min, washed again with bidistilled water and then dried at room temperature before use. Solutions The aggressive solutions of 1.0 M HCl was prepared by dilution of analytical grade 37% HCl with distilled water. The concentration range of quinoline derivatives used was 1 ×10-5M to 5 ×10-3 M. Corrosion tests Weight loss Gravimetric measurements were carried out at definite time interval of 6 h at room temperature using an analytical balance (precision ± 0.1 mg). The mild steel specimens used have a rectangular form (length = 2 cm, width = 2 cm, thickness = 0.08 cm). Gravimetric experiments were carried out in a double glass cell equipped with a thermostated cooling condenser containing 80 mL of test solution. After immersion period, the steel specimens were withdrawn, carefully rinsed with bidistilled water, ultrasonic cleaning in acetone, dried at room temperature and then weighed. Electrochemical impedance spectroscopy The electrochemical measurements were carried out using Volta lab (Tacussel- Radiometer PGZ 100) potentiostate and controlled by Tacussel corrosion analysis software model (Volta master 4) at under static condition. The corrosion cell used had three electrodes. The reference electrode was a saturated calomel electrode (SCE). A platinum electrode was used as auxiliary electrode of surface area of 1 cm2. The working electrode was mild steel. All potentials given in this study were referred to this reference electrode. The working electrode was immersed in test solution for 30 minutes to a establish steady state open circuit potential (Eocp). After measuring the Eocp, the electrochemical measurements were performed. All electrochemical tests have been performed at 303 K. The EIS experiments were conducted in the frequency range with high limit of 100 kHz and different low limit 10 mHz at open circuit potential, with 10 points per decade, at the rest potential, after 30 min of acid immersion, by applying 10 mV ac voltage peak-to-peak. Nyquist plots were made from these experiments. Potentiodynamic polarization The electrochemical behaviour of mild steel sample in inhibited and uninhibited solution was studied by recording anodic and cathodic potentiodynamic polarization curves. Measurements were performed in the 1.0 M HCl solution containing different concentrations of the tested inhibitors by changing the electrode potential automatically from 800 to -200 mV versus corrosion potential at a scan rate of 2mV.s-1. The linear Tafel segments of anodic and cathodic curves were extrapolated to corrosion potential to obtain corrosion current densities (icorr). Inhibitors In continuation of our research for developing corrosion inhibitors with high effectiveness and efficiency, the present paper explores a systematic study to ascertain the inhibitive action of synthesized quinoline derivatives, on corrosion of mild steel in 1.0 M HCl solution by using weight loss measurement, potentiodynamic polarization and AC impedance. Figure 1 shows the molecular structure of the quinoline derivatives utilised in this investigation. The detail of synthesis methods referenced from the published article[6,23]

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R. Salghi et al Der Pharmacia Lettre, 2016, 8 (18):158-166 ______________________________________________________________________________ H N

N OH 5-((benzylamino)methyl)quinolin-8-ol (8QN2)

ethyl 2-(((8-hydroxyquinolin-5-yl)methyl)amino)acetate (8QN1)

5-(azidomethyl)quinolin-8-ol (8QN3) Figure 1: Chemicals structures of quinoline derivatives

RESULTS AND DISCUSSION Effect of concentration inhibitor Weight loss The results obtained from weight loss study are given in Table 1. It can be seen from the results that on increasing the concentration of inhibitors, inhibition efficiency increases from 78 to 90% and shows the following order of inhibition 8QN3 > 8QN2 > 8QN1. The corrosion rate, CR (mg/cm2×h), surface coverage (θ) and inhibition efficiency ηw (%) of each concentration were calculated using the following equations[1]:

W=

∆m St

(1)

 Wuninh − Winh   ×100  Wuninh 

(2)

ηW = 

Where ∆m is the average weight loss (mg), S is the surface area of specimens (cm2), and t is the immersion time (h), Wuninh and Winh are corrosion rates in the absence and presence of inhibitor, respectively. Table 1. Effect of 8QNs concentrations on corrosion data of mild steel in 1.0 M HCl Composé HCl

8QN3

8QN2

8QN1

Concentration (mol/L) 1

(mg/cm2 × h) 1.1350

(%) -

× × × ×

0.1135 0.1589 0.2270 0.2497

90 86 80 78

× × × ×

0.1362 0.1929 0.2837 0.3518

88 83 75 69

× × × ×

0.1589 0.2270 0.3178 0.4426

86 80 72 61

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R. Salghi et al Der Pharmacia Lettre, 2016, 8 (18):158-166 ______________________________________________________________________________ Corrosion inhibition performance of a compound depends upon its ability to get adsorbed on metal surfaces. In our investigation, we have taken quinoline derivatives containing π electrons and heteroatoms (N, O) by which they can easily get adsorbed onto the metal surface and form a protective layer thereby preventing the corrosion[24,25]. Electrochemical impedance spectroscopy Fig. 2 shows the impedance responses of mild steel in the absence and presence of quinoline derivatives. The impedance parameters calculated from these plots are given in Table 2. The Nyquist plots exhibit one capacitive loop in the absence and presence of inhibitors suggesting that corrosion of mild steel was charge transfer controlled[10]. The diameter of the capacitive loops increases with increasing concentrations of inhibitors, which suggests that all the three compounds act as effective corrosion inhibitors for mild steel and show the following order of inhibition 8QN3 > 8QN2 > 8QN1[16]. The increased diameter of the Nyquist plots in the presence of QNs suggested also that values of charged transfer resistance (Rct) increase due to formation of protective film[11,14]. The electrochemical parameters, including Rct, Q and n, obtained from fitting the recorded EIS data using the electrical circuit of Figure 3 are listed in Table 2. The impedance of the CPE is expressed as follows[17].

Z CPE =

1 Q ( jω )

(3)

n

Where Q is the CPE constant, n is the phase shift which can be explained as a degree of surface inhomogeneity, j is the imaginary unit and ω is the angular frequency. Depending on the values of n, CPE can represent resistance (n=0), capacitance (n=1), inductance (n= -1) and Warburg impedance (n=0.5). The values of the interfacial capacitance Cdl can be calculated from CPE parameter values Q and n using the expression[30]:

(

Cdl = Q × R1− n

)

1/ n

(4)

The Rct values were used to calculate the inhibition efficiency, ηEIS(%), (listed in Table 2), using the following equation:

ηEIS % =

(5)

Rct° and Rcti are the charge transfer resistance in absence and in presence of inhibitor, respectively. 300

14

4 2 0 0

5

10

15

20

25

30

200

35

Zr (ohm cm2)

100

-Zi (ohm cm2)

6

10

250

2

-Zi (ohm cm2)

2

150

8

8QN3

Blank

12

-3 5 x 10 M -3 1 x 10 M -4 1 x 10 M -5 1 x 10 M

10

200

14

8QN2

Blank

12

-Zi (Ω x cm )

250

-Zi (Ω x cm )

Where

Rcti − Rct° ×100 Rcti

-3 5 x 10 M -3 1 x 10 M -4 1 x 10 M -5 1 x 10 M

8 6 4 2 0

150

0

5

10

15

20

25

30

35

Zr (ohm cm2)

100 50

50 0 0

50

100

150

200

250

0 0

50

2

Zr (Ω x cm )

100

150

200

250

300

2

Zr (Ω x cm )

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R. Salghi et al Der Pharmacia Lettre, 2016, 8 (18):158-166 ______________________________________________________________________________ 200

14

8QN1

Blank

12

-3 5 x 10 M -3 1 x 10 M -4 1 x 10 M -5 1 x 10 M

-Zi (ohm cm2)

10

2

-Zi (Ω x cm )

150

8 6 4 2 0

100

0

5

10

15

20

25

30

35

Zr (ohm cm2)

50

0 0

50

100

150

200

2

Zr ( Ω x cm )

Figure 2: Nyquist diagrams of mild steel with different concentrations of 8QNs at 303K

Figure 3: Equivalent electrical circuit model

Inspection of the Table 2 reveals that values of Rct increase with increasing 8QNs concentration suggesting that extent of surface coverage and η% increases with inhibitor concentration. The values of Cdl decreased (Table 2) with the addition of 8QNs, which is probably due to the decrease in the local dielectric constant and/or an increase in the thickness of the electrical double layer, suggesting that the 8QNs strongly adsorbed over the mild steel surface[5,7,11]. Table 2. Electrochemical impedance parameters for corrosion of mild steel in acid medium at various contents of 8QNs at 303 K Inhibitor Blank

Concentration ( ) 1.0

8QN3

8QN2

8QN1

×

Ɵ

( × ) 29.35

0.89

1.7610

/ ) 91.86

(

× × × ×

271 206 135 103

0.88 0.87 0.86 0.83

0.2998 0.4003 0.7135 1.0701

× × × ×

215 172 122 95

0.83 0.84 0.84 0.81

× × × ×

187 150 99 81

0.86 0.82 0.81 0.83

(%) -

-

15.55 19.54 33.51 42.51

89 85 78 71

0.89 0.85 0.78 0.71

0.4419 0.5502 0.8989 1.1743

17.02 22.64 38.05 40.91

86 82 75 69

0.86 0.82 0.75 0.69

0.5272 0.7865 1.1687 1.3321

24.85 29.67 41.06 52.68

84 80 70 63

0.84 0.80 0.70 0.63

(

)

Polarization curves The polarization curves for mild steel in the absence and presence of inhibitors of different concentrations are shown in Figure 4. The values obtained from polarization curves such as corrosion current densities (icorr), corrosion potential (Ecorr), and Tafel slope (βc) are listed in Table 2. The icorr values were used to calculate the inhibition efficiency, ηPDP(%), (listed in Table 3), using the following equation[16]:

ηPDP % = Where,

Icorr − Icorr (i )

Icorr

Icorr and

×100

(6)

Icorr(i) are the corrosion current density in absence and presence of inhibitor, respectively.

The obtained results show that inhibition efficiency increases with decreasing values of icorr and the highest inhibition efficiency 90% is obtained for 8QN3 at 5×10-3 M.

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R. Salghi et al Der Pharmacia Lettre, 2016, 8 (18):158-166 ______________________________________________________________________________ 1000

1000

8QN3

100

100

10

10 2

I (mA/cm )

2

I (mA/cm )

8QN2

1 0.1

0.01 0.001 1E-4 -800

Blank -3 5 x 10 M -3 1 x 10 M -4 1 x 10 M -5 1 x 10 M -700

1 0.1

0.01 0.001

-600

-500 -400 E (mV/SCE)

-300

Blank -3 5 x 10 M -3 1 x 10 M -4 1 x 10 M -5 1 x 10 M

1E-4 -800

-200

-700

-600

-500 -400 E (mV/SCE)

-300

-200

1000 8QN1 100

2

I (mA/cm )

10 1 0.1

0.01 0.001 1E-4 -800

Blank -3 5 x 10 M -3 1 x 10 M -4 1 x 10 M -5 1 x 10 M -700

-600

-500 -400 E (mV/SCE)

-300

-200

Figure 4. Potentiodynamic polarization curves of mild steel in 1.0 M HCl in the presence of different concentrations of 8QNs at 303 K

From Figure 4 it can be seen that the addition of an inhibitor modifies both cathodic and anodic polarization branches and shifts the Ecorr towards the negative direction as compared to an inhibitor-free solution. As previously reported in the presence of inhibitor if Ecorr shifts more than 85 mV with respect to Ecorr in uninhibited solution, the inhibitor can be considered as cathodic or anodic type otherwise it is of mixed type[35,36]. The Ecorr values of 8QN1, 8QN2, and 8QN3 suggested that these compounds show the mixed type of inhibition with Ecorr shift in the negative direction which is an indication of cathodic predominance[37]. The negative shift of Ecorr indicates more adsorption of the inhibitor on the cathodic sites and predominantly controls cathodic reactions[38]. The presence of all the three inhibitors causes a decrease in icorr values in all concentrations. Table 3. Electrochemical parameters of mild steel at various concentrations of 8QNs in 1.0 M HCl and corresponding inhibition efficiency Inhibitor HCl

8QN3

8QN2

8QN1

− (mV/SCE) 496

− (mV dec-1) 150.19

! (µA cm-2) 564

× × × ×

538 539 536 537

170 167 171 168

× × × ×

538 539 536 537

× × × ×

543 542 541 539

Concentration (M) 1.0

(%)

Ɵ

-

-

56 79 111 145

90 86 80 74

0.9 0.86 0.80 0.74

152 155 152 154

62 92 128 155

89 83 77 72

0.89 0.83 0.77 0.72

159 157 153 158

85 82 73 60

0.85 0.82 0.73 0.60

0.85 0.82 0.73 0.60

"

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R. Salghi et al Der Pharmacia Lettre, 2016, 8 (18):158-166 ______________________________________________________________________________ Adsorption isotherm and standard adsorption free energy The adsorption isotherm can be determined by assuming that the inhibition effect was mainly due to adsorption at the metal/solution interface. The adsorption process depends upon the electronic characteristics of the 8QNs, the nature of the metal surface, the temperature, steric effects and the varying degrees of the surface-site activity. A typical adsorption process involves the replacement of the adsorbed water molecule (H2Oads) by inhibitor molecules present in aqueous solution (Orgaq) at metal/electrolyte interface as represented below[39]: Orgaq + xH2Oads ↔ Orgads + xH2Oaq where x is the number of water molecules replaced by one molecule of organic inhibitors. An attempt was made to plot the values of surface coverage (θ) derived from weight loss experiment against different 8QNs concentrations in order to obtained the best adsorption isotherm. Several adsorption isotherms such as Langmuir, Temkin and Freundluich isotherms were tested. In our present study the Langmuir isotherm gave the best fit which can be best represented by following equation[40]:

C inh

θ

=

1 + C inh K ads

(7)

Where Cinh is the concentration of inhibitor and Kads the adsorptive equilibrium constant. Figure 5 shows the curves of the variation of Cinh / θ according to the concentration Cinh for the quinoline compounds. The linearity of these curves indicates that the adsorption of our inhibitors on the surface of mild steel in 1 M HCl, is according to the Langmuir isotherm model. The validity of this approach is confirmed by the strong correlation (R2= 0.999). The values of Kads obtained from the reciprocal of intercept of Langmuir isotherm line are listed in Table 6, together ° calculated from the equation: with the values of the Gibbs free energy of adsorption ∆Gads

K ads

° ∆Gads 1 ) exp(− ) =( 55.5 RT

(8)

Where R is gas constant and T is absolute temperature of experiment and the constant value of 55.5 is the concentration of water in solution.

0.006 8QN3 8QN2 8QN1

0.005

Cinh/θ

0.004 0.003 0.002 0.001 0.000 0.000

0.001

0.002

0.003

0.004

0.005

C (M)

Figure 5. Adsorption isotherm according to Langmuir’s model derived from weight loss measurement Table 4. Thermodynamic parameters for the adsorption of 8QNs in 1 M HCl on the carbon steel at 303 K Inhibitors

R2

8QN3 8QN2 8QN1

0.99994 0.99990 0.99992

Kads (L/mol) 46794 34319 27413

∆$ads (kJ/mol) -37 -36 -35

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R. Salghi et al Der Pharmacia Lettre, 2016, 8 (18):158-166 ______________________________________________________________________________ Generally, a higher value of Kads associated with higher tendency to adsorb on mild steel surface. In our present study the Kads value of different 8QNs follows the order: 8QN3 > 8QN2 > 8QN1 which is in accordance with the order of the η%. Literature study reveals that the value of ∆$ads up to −20 kJ/mol or less negative is related to the electrostatic interactions between inhibitor and metallic surfaces (physisorption), while the value of ∆$ads is around −40 kJ/mol or more negative related to the charge sharing between inhibitor and metallic surfaces (chemisorption)[41]. In our present investigation values of ∆Gads vary from −37 to −35 kJ/mol (Table 4) that signifying the both physical and chemical i.e. physiochemisorption of 8QNs[16,25,41]. The negative sign of ∆Gads ensures the spontaneity of the adsorption process[41]. CONCLUSION Results show that 8QNs act as good corrosion inhibitors for mild steel in 1 M HCl and their inhibition efficiency increases with increasing concentration. The negative value of ∆Gads suggests that 8QNs adsorb spontaneously and their adsorption obeys the Langmuir adsorption isotherm. The polarization study revealed that the 8QNs act as mixed type inhibitors with cathodic predominance. The presence of the 8s increases the charge transfer values and therefore inhibits mild steel corrosion. REFERENCES [1] B El Makrini, H Lgaz, K Toumiat, R Salghi, S Jodeh, G Hanbali, M Belkhaouda, and M Zougagh, Res. J. Pharm. Biol. Chem. Sci. 2016, 7, 2277. [2] M Larouj, H Lgaz, H Serrar, H Zarrok, H Bourazmi, A Zarrouk, A Elmidaoui, A Guenbour, S Boukhris, and H Oudda, J. Mater. Environ. Sci. 2015, 6, 3251. [3] L Adardour, H Lgaz, R Salghi, M Larouj, S Jodeh, M Zougagh, O Hamed, and H Oudda, Pharm. Lett. 2016, 8, 212. [4] H Lgaz, A Anejjar, R Salghi, S Jodeh, M Zougagh, I Warad, M Larouj, and P Sims, Int. J. Corros. Scale Inhib. 2016, 5, 209. [5] M Saadouni, M Larouj, R Salghi, H Lgaz, S Jodeh, M Zougagh, and A Souizi, Pharm. Lett. 2016, 8, 65. [6] H Lgaz, S Rachid, M Larouj, M Elfaydy, S Jodeh, H Abbout, B Lakhrissi, K Toumiat, and H Oudda, Moroc. J. Chem. Mor. 2016, 4, 592. [7] L Adardour, H Lgaz, R Salghi, M Larouj, S Jodeh, M Zougagh, O Hamed, and M Taleb, Pharm. Lett. 2016, 8, 173. [8] L Adardour, H Lgaz, R Salghi, M Larouj, S Jodeh, M Zougagh, I Warad, and H Oudda, Pharm. Lett. 2016, 8, 126. [9] H Lgaz, R Salghi, and S Jodeh, Int. J. Corros. Scale Inhib. 2016, 5, 347. [10] H Lgaz, M Larouj, M Belkhaouda, R Salghi, S Jodeh, I Warad, H Oudda, and A Chetouani, Moroc. J. Chem. 2016, 4, 101. [11] B El Makrini, K Toumiat, H Lgaz, R Salghi, S Jodeh, G Hanbali, M Belkhaouda, and M Zougagh, Res. J. Pharm. Biol. Chem. Sci. 2016, 7, 2286. [12] L Adardour, M Larouj, H Lgaz, M Belkhaouda, R Salghi, S Jodeh, A Salman, H Oudda, and M Taleb, Pharma Chem. 2016, 8, 152. [13] N Lotfi, H Lgaz, M Belkhaouda, M Larouj, R Salghi, S Jodeh, H Oudda, and B Hammouti, Arab. J. Chem. Environ. Res. 2015, 1, 13. [14] M Larouj, H Lgaz, S Rachid, S Jodeh, M Messali, M Zougagh, H Oudda, and A Chetouni, Moroc. J. Chem. 2016, 4, 567. [15] L Afia, M Larouj, H Lgaz, R Salghi, S Jodeh, S Samhan, and M Zougagh, Pharma Chem. 2016, 8, 22. [16] K Toumiat, Y El Aoufir, H Lgaz, R Salghi, S Jodeh, M Zougagh, and H Oudda, Res. J. Pharm. Biol. Chem. Sci. 2016, 7, 1210. [17] M Saadouni, M Larouj, R Salghi, H Lgaz, S Jodeh, M Zougagh, and A Souizi, Pharm. Lett. 2016, 8, 96. [18] L Afia, M Larouj, R Salghi, S Jodeh, M Zougagh, A Rasem Hasan, and H Lgaz, Pharma Chem. 2016, 8, 166. [19] B El Makrini, M Larouj, H Lgaz, R Salghi, A Salman, M Belkhaouda, S Jodeh, M Zougagh, and H Oudda, Pharma Chem. 2016, 8, 227. [20] M Larouj, M Belkhaouda, H Lgaz, R Salghi, S Jodeh, S Samhan, H Serrar, S Boukhris, M Zougagh, and H Oudda, Pharma Chem. 2016, 8, 114. [21] M Larouj, H Lgaz, S Rachid, H Oudda, S Jodeh, and A Chetouani, Moroc. J. Chem. 2016, 4, 425. [22] Y El Aoufir, H Lgaz, K Toumiat, R Salghi, S Jodeh, M Zougagh, A Guenbour, and H Oudda, Res. J. Pharm. Biol. Chem. Sci. 2016, 7, 1200. [23] M Elfaydy, H Lgaz, R Salghi, M Larouj, S Jodeh, M Rbaa, H Oudda, K Toumiat, and B Lakhrissi, J. Mater. Environ. Sci. 2016, 7, 3193. [24] K Toumiat, Y El Aoufir, H Lgaz, R Salghi, S Jodeh, M Zougagh, and H Oudda, Res. J. Pharm. Biol. Chem. Sci. 2016, 7, 1209.

165


R. Salghi et al Der Pharmacia Lettre, 2016, 8 (18):158-166 ______________________________________________________________________________ [25] Y El Aoufir, H Lgaz, K Toumiat, R Salghi, S Jodeh, M Zougagh, A Guenbour, and H Oudda, Res. J. Pharm. Biol. Chem. Sci. 2016, 7, 1219. [26] A Bousskri, R Salghi, A Anejjar, S Jodeh, M A Quraishi, M Larouj, H Lgaz, M Messali, S Samhan, and M Zougagh, Pharma Chem. 2016, 8, 67. [27] H Lgaz, O Benali, R Salghi, S Jodeh, M Larouj, O Hamed, M Messali, S Samhan, M Zougagh, and H Oudda, Pharma Chem. 2016, 8, 172. [28] H Lgaz, Y ELaoufir, Y Ramli, M Larouj, H Zarrok, R Salghi, A Zarrouk, A Elmidaoui, A Guenbour, EM Essassi, and H Oudda, Pharma Chem. 2015, 7, 36. [29] O Krim, S Jodeh, M Messali, B Hammouti, A Elidrissi, K Khaled, R Salghi, and H Lgaz, Port. Electrochimica Acta 2016, 34, 213. [30] M J Reddy, C Verma, EE Ebenso, KK Singh, MA Quraishi, Int J Electrochem Sci, 2014, 9, 4884–4899 [31] B El Makrini, H Lgaz, M Larouj, R Salghi, A Rasem Hasan, M Belkhaouda, S Jodeh, M Zougagh, and H Oudda, Pharma Chem. 2016, 8, 256. [32] H Lgaz, R Salghi, S Jodeh, Y Ramli, M Larouj, K Toumiat, MA Quraishi, H Oudda, and W Jodeh, J. Steel Struct. Constr. 2016, 2, 1. [33] S K Saha, P Ghosh, A Hens, N C Murmu, and P Banerjee, Phys. E Low-Dimens. Syst. Nanostructures 2015, 66, 332. [34] S K Saha, M Murmu, N C Murmu, and P Banerjee, J. Mol. Liq. 2016, 224, Part A, 629. [35] K Zhang, W Yang, B Xu, Y Liu, X Yin, and Y Chen, J. Taiwan Inst. Chem. Eng. 2015, 57, 167. [36] B Xu, Y Ji, X Zhang, X Jin, W Yang, and Y Chen, J. Taiwan Inst. Chem. Eng. 2016, 59, 526. [37] A A Farag, A S Ismail, and M A Migahed, J. Mol. Liq. 2015, 211, 915. [38] D K Singh, S Kumar, G Udayabhanu, and R P John, J. Mol. Liq. 2016, 216, 738. [39] C Verma, M A Quraishi, and A Singh, J. Mol. Liq. 2015, 212, 804. [40] C Verma, E E Ebenso, I Bahadur, I B Obot, and M A Quraishi, J. Mol. Liq. 2015, 212, 209. [41] C Verma, M A Quraishi, E E Ebenso, I B Obot, and A El Assyry, J. Mol. Liq. 2016, 219, 647. [42] D K Yadav, B Maiti, and M Quraishi, Corros. Sci. 2010, 52, 3586. [43] I Obot and N Obi-Egbedi, Mater. Chem. Phys. 2010, 122, 325. [44] S Deng, X Li, and X Xie, Corros. Sci. 2014, 80, 276.

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